Localization of glyoxylate dehydrogenase and glyoxylate-complex molecules in the rat prefrontal cortex: enzymohistochemical and immunocytochemical study

Glyoxylic acid is synthesized and catabolized in cells of vertebrates; several pathways have been described. In previous papers, we have demonstrated the localization in some areas of the rat cerebral cortex both of beta-NAD-dependent glyoxylate dehydrogenase (glyoDH), using an enzymohistochemical method, and of glyoxylate-complex molecules, using immunocytochemical procedures. In this study we have applied these two techniques in various areas of the prefrontal cortex with different histological cytoarchitecture. GlyoDH has been located in most neurons, in some glial cells, and in capillary wall structures in all cortical layers of all areas of the rat prefrontal cortex. Antibodies against glyoxylate-complex molecules showed positive immunoreactivity in scattered neurons, mostly of multipolar or stellate appearance, from layers III, IV, and V in the medial precentral area, but not in cortical areas 24, 25, or 32 of the prefrontal cortex. Immunoreaction was found in the periphery of neuronal perikarya and in some of their processes. These results demonstrate the existence of a particular area-dependent neuronal cortical system, of specific but uncertain function, related to glyoxylic acid and/or glyoxylate compounds. At the electron microscope level, positive reaction was associated with synaptic sites, axonal filaments, glial cells, and several components of the blood-brain barrier. These localizations suggest the involvement of glyoxylate derivatives in synaptic functioning and also in glial cell functions.     

Biological Response Modifier Activity of an Exopolysaccharide from Paenibacillus jamilae CP-7

An extracellular polysaccharide was purified from culture supernatants of Paenibacillus jamilae CP-7, a gram-positive bacillus that was isolated from compost prepared with olive mill wastewaters. The extracellular polysaccharide was produced under aerobic conditions in a medium containing olive mill wastewaters (80% [vol/vol]). This exopolymer had a low level of acute toxicity when it is administered to BALB/c mice by the intraperitoneal route. Interesting immunomodulatory effects were detected when mice were given 10 mg of exopolysaccharide per kg of body weight; the proliferative responses of splenocytes to B-cell and T-cell mitogens were suppressed, the in vitro levels of production of gamma interferon and granulocyte-macrophage colony-stimulating factor by unstimulated and lipopolysaccharide-stimulated splenocytes were enhanced, and the levels of resistance to the intracellular pathogen Listeria monocytogenes was increased in mice. Also, the exopolysaccharide was able to induce lymphocyte proliferation in vitro. We conclude that P. jamilae produces an exopolysaccharide with interesting immunomodulatory properties.     

Exogenous attention to facial vs non-facial emotional visual stimuli

The capacity of the two types of non-symbolic emotional stimuli most widely used in research on affective processes, faces and (non-facial) emotional scenes, to capture exogenous attention, was compared. Negative, positive and neutral faces and affective scenes were presented as distracters to 34 participants while they carried out a demanding digit categorization task. Behavioral (reaction times and number of errors) and electrophysiological (event-related potentials—ERPs) indices of exogenous attention were analyzed. Globally, facial expressions and emotional scenes showed similar capabilities to attract exogenous attention. Electrophysiologically, attentional capture was reflected in the P2a component of ERPs at the scalp level, and in left precentral areas at the source level. Negatively charged faces and scenes elicited maximal P2a/precentral gyrus activity. In the case of scenes, this negativity bias was also evident at the behavioral level. Additionally, a specific effect of facial distracters was observed in N170 at the scalp level, and in the fusiform gyrus and inferior parietal lobule at the source level. This effect revealed maximal attention to positive expressions. This facial positivity offset was also observed at the behavioral level. Taken together, the present results indicate that faces and non-facial scenes elicit partially different and, to some extent, complementary exogenous attention mechanisms.     

Organizing pneumonia adjacent to lung cancer: frequency and clinico-pathologic features.

In order to assess the frequency of peripheral organizing pneumonia (OP) in patients with resected lung tumours and to describe its differential features, a cross-sectional study with prospective data collection was realized in a community teaching hospital. Demographic and clinical data were collected from clinical records. The lung specimens removed with a curative purpose in 89 consecutive patients with lung tumours were studied and the clinical and pathological characteristics of patients with and without OP were compared. In 33 of 89 patients (37%) included, OP in the vicinity of neoplasm was found. Areas of other types of fibrosis were evident in 21 patients (24%). Male gender, smoker, epidermoid histological type and the presence of lipid pneumonia were found with a significant higher frequency in patients with OP. Although without significant differences, the presence of symptoms and the bronchial stenosis were found more frequently in patients with OP. In conclusion, OP pattern adjacent to lung cancer, frequently associated to lipid pneumonia, is a common pathological finding. Male gender, a history of tobacco use and epidermoid histological type appear as risk factors for developing this pathologic pattern. Given the lack of distinctive clinico-pathological features, cancer adjacent OP could be confounded with other etiologic forms of this fibrotic process.     

In vitro interactions of licensed and novel antifungal drugs against Fusarium spp

We have studied the in vitro interactions of amphotericin B (AMB) with terbinafine (TBF), itraconazole, voriconazole (VCZ), albaconazole, and ravuconazole (RVZ), as well as TBF combined with the same azoles, against 11 isolates of Fusarium spp. using the fractional inhibitory concentration index. The highest percentage of synergistic interactions was observed for the combinations AMB-RVZ, TBF-VCZ, and TBF-RCZ.     

A novel murine model of cerebral scedosporiosis: lack of efficacy of amphotericin B

OBJECTIVES: Cerebral scedosporiosis is a life-threatening infection that is difficult to treat. The aim of this work was to develop a murine model of cerebral infection by Scedosporium apiospermum using intracranial inoculation and to use this model to evaluate the efficacy of amphotericin B deoxycholate and liposomal amphotericin B. METHODS: Mice were rendered neutropenic by intraperitoneal cyclophosphamide and intravenous (iv) 5-fluorouracil administration. Animals were infected with iv or intracranial inoculation of 1 x 10(4), 5 x 10(4) or 5 x 10(5) cfu of a clinical strain of S. apiospermum. Tissue burden reduction was determined in kidneys and brain 4 days after the infection. Efficacy of amphotericin B and liposomal amphotericin B (0.8 mg/kg/day intraperitoneally and 40 mg/kg/day iv, respectively) was evaluated in neutropenic mice infected iv or intracranially with 5 x 10(4) cfu. Survival was analysed with the log-rank test. Fungal burden values of different groups were compared using the Mann-Whitney U-test. RESULTS: In our model, intracranial infection produced a higher fungal load in the brain and a lower fungal load in the kidney than iv inoculation. Survival of animals infected intracranially and treated with amphotericin B or liposomal amphotericin B (mean survival time = 8.3 and 9.2 days, respectively) was not different from the control group (P=0.58 and 0.85, respectively). CONCLUSIONS: We have developed a murine model of cerebral scedosporiosis, which may be useful for studying various pathological aspects of this infection and evaluating new therapeutic approaches. Amphotericin B and liposomal amphotericin B were unable to resolve the infection.     

Correlation between in vitro susceptibility of Scedosporium apiospermum to voriconazole and in vivo outcome of scedosporiosis in guinea pigs

We have evaluated the efficacy of voriconazole (VRC) in a systemic infection by Scedosporium apiospermum in immunodepressed guinea pigs. Animals were infected with two strains; one required a VRC MIC of 0.5 to 1 microg/ml, common for this fungus, and the other required a high MIC (8 microg/ml), unusual in this species. VRC prolonged survival and reduced fungal load in kidney and brain tissues of the animals infected with the first strain but was unable to prolong survival or to reduce fungal load in brain tissue for the latter strain.     

In vitro activities of new antifungal agents against Chaetomium spp. and inoculum standardization

Chaetomium is an unusual etiological agent of human infections, but the mortality rate among immunocompromised patients is considerably greater than that among nonimmunocompromised individuals. We investigated the in vitro antifungal susceptibilities to novel antifungal agents of 19 strains belonging to three species of Chaetomium which have been involved in human infections, i.e., Chaetomium globosum, C. atrobrunneum, and C. nigricolor, and one strain of the closely related species Achaetomium strumarium. A modification of the NCCLS reference microdilution method (M38-A) was used to evaluate the in vitro activities of ravuconazole, voriconazole, albaconazole, and micafungin. Micafungin was not active at all, while the geometric mean MICs and minimum effective concentrations of the three triazoles were less than 0.5 and 0.4 micro g/ml, respectively.